/*
 * Copyright 2002-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.web.client;

import org.springframework.http.HttpHeaders;
import org.springframework.lang.Nullable;

import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

/**
 * Common base class for exceptions that contain actual HTTP response data.
 *
 * @author Rossen Stoyanchev
 * @since 4.3
 */
public class RestClientResponseException extends RestClientException {

    private static final long serialVersionUID = -8803556342728481792L;

    private static final Charset DEFAULT_CHARSET = StandardCharsets.ISO_8859_1;


    private final int rawStatusCode;

    private final String statusText;

    private final byte[] responseBody;

    @Nullable
    private final HttpHeaders responseHeaders;

    @Nullable
    private final String responseCharset;


    /**
     * Construct a new instance of with the given response data.
     *
     * @param statusCode      the raw status code value
     * @param statusText      the status text
     * @param responseHeaders the response headers (may be {@code null})
     * @param responseBody    the response body content (may be {@code null})
     * @param responseCharset the response body charset (may be {@code null})
     */
    public RestClientResponseException(String message, int statusCode, String statusText,
                                       @Nullable HttpHeaders responseHeaders, @Nullable byte[] responseBody, @Nullable Charset responseCharset) {

        super(message);
        this.rawStatusCode = statusCode;
        this.statusText = statusText;
        this.responseHeaders = responseHeaders;
        this.responseBody = (responseBody != null ? responseBody : new byte[0]);
        this.responseCharset = (responseCharset != null ? responseCharset.name() : null);
    }


    /**
     * Return the raw HTTP status code value.
     */
    public int getRawStatusCode() {
        return this.rawStatusCode;
    }

    /**
     * Return the HTTP status text.
     */
    public String getStatusText() {
        return this.statusText;
    }

    /**
     * Return the HTTP response headers.
     */
    @Nullable
    public HttpHeaders getResponseHeaders() {
        return this.responseHeaders;
    }

    /**
     * Return the response body as a byte array.
     */
    public byte[] getResponseBodyAsByteArray() {
        return this.responseBody;
    }

    /**
     * Return the response body converted to String. The charset used is that
     * of the response "Content-Type" or otherwise {@code "UTF-8"}.
     */
    public String getResponseBodyAsString() {
        return getResponseBodyAsString(DEFAULT_CHARSET);
    }

    /**
     * Return the response body converted to String. The charset used is that
     * of the response "Content-Type" or otherwise the one given.
     *
     * @param fallbackCharset the charset to use on if the response doesn't specify.
     * @since 5.1.11
     */
    public String getResponseBodyAsString(Charset fallbackCharset) {
        if (this.responseCharset == null) {
            return new String(this.responseBody, fallbackCharset);
        }
        try {
            return new String(this.responseBody, this.responseCharset);
        }
        catch (UnsupportedEncodingException ex) {
            // should not occur
            throw new IllegalStateException(ex);
        }
    }

}
